This invention lies in the field of vehicle leveling systems. More particularly, it is in the field of pneumatic leveling systems in which compressed air is supplied to one or more leveling cylinders by an automatic gravity controlled valving system.
In the prior art vehicles such as automobile trailers or recreational vehicles, farm and industrial machines as well as other portable equipment requiring leveling have been leveled by manual means operating screw or hydraulic levelers at each of the corners of the vehicle. These require much repetition of raising or lowering until a balanced condition of the cylinders is reached at which time the floor of the vehicle is leveled. There has been a need for an automatic leveling system which, on one operation, controls the flow of compressed air to a plurality of lifting cylinders at each corner of the vehicle, so as to attain a horizontal condition automatically, simply and quickly.